Eevebsing geae for steam engines



2 Shee-ts--Sheet 1 (No Moflel.) I

A. R. LAMB. REVERSING GEAR EUR STEAM ENGINES. Y No. 514,479. PatentedFeb. 13, 1894.

(No Model.) v 2 sheets-sheet 2A A. R. LAM-B. REVERSING GEAR FORSTEAMV'ENGINES. No. 514,479.

Patented Feb. 113, 1894.

us mmonAL umoonAPHms coMPANY.

w ma o UNrrED STATES PATENT Erica.

ALEXANDER R. LAMB, OF FENELON FALLS, CANADA.

REVERSlNG-GEAR FOR STEAM-ENGINES.

SEECIFIGATION forming part of Letters Patent No. 514,479, dated February13, 1894.

Application filed June 2S, 1893. Serial No. I!=78,63l. (No model.)

To .all whom it may concern:

Be it known that I, ALEXANDER R. LAMB, of Fenelon Falls, in the countyof Victoria, Province of Ontario, Canada, have invented certain new andusefullrnprovements in Reversing-Gear for Steam-Engines; and I herebydeclare the following to be a full, clear, and exactdescription of thesame.

This invention relates to a reversing gear for steam engines, and moreparticularly to a reversing gear for that style of steam engine employedin the smaller class of steam boats, and the object of the invention isto construct the reversing gear in such a manner that the backward andforward movements et the engine are entirely under the control of asingle eccentric rod, and the invention consists essentially of. thedevice hereinafter more fully Set forth.

In the drawingsz-Figure lis a front elevation of the device, showing theengine about to commence its forward stroke. Fig. 2 is a view of thesame, showing it about to commence the backward stroke.

Like nu morals of reference refer tolike parts throughout thespecification and drawings.

The reversing gear consists of an eccentric rod l jointed at its upperend to the lower end of the valve rod 2 which operates the valves 3. Thelower end of the eccentric rod l is provided with the opposite collarsl2, loosely engaging a pair of upwardly projecting pins 3 which are madefast in the lugs 3" of the eccentric straps 3, in which works theeccentric 4, mounted on the shaft 5, 'and made fast to the frame work ofthe engine is a horizontally-arranged curved link 7, and working in thelink 7 is the link-block end S of the link arm 8 the other end 8 ofwhich is pivotally connected to the eccentric rod 7 near its lower end.Connected to the block end 8 of the link arm 8, is one end of a rod 9,while the other end of the rod is connected to the reach rod l0. Whenthe end 8 of the link arm Sis l at the end 7a of the link 7, or in theposition shown in Fig. l of the drawings the engine will run in aforwarddirection. When however, the end 8a of the link arm 8 is moved to theend 'i'b of the link 7, as shown in Fig. 2 of the drawings, the enginewill commence its backward stroke.

It the engine be moved off its center in the direction of the arrow inFig. l, the eccentric rod `will descend and open the upper steam portfrom the steam chest into the cylinder. After the engine has passed themiddle ofits stroke, the valve will close the upper steam port and openthe lower one. If the engine be moved ed its center in the direction ofthe arrow in Fig. 2, the eccentric rod will move the valve rod to openthelower steam port from the steam chest into the cylinder, and when theengine has passed the middle of its stroke it will move the valve rod toclose the lower valve, and open the upper one, this action beingcontinued while the engine is in motion.

By means of a device of this description the cost of the engine can begreatly reduced and the construction and operations of the enginegreatly simplified.

By reason of the pivotal connection of the link-arm 8, with theeccentric rod, it will be apparent that one end of this arm will swingin the arc of a circle up and down as the lower end of the eccentric rodis swung laterally to either side of the shaft 5 by the movement of theeccentric 4, and such arm will therefore permit a sufiicient reciprocatory movement of the eccentric rod to insure the proper opening andclosing of the ports in the steam chest.

Assumingthe gearing to be in the position shown in Fig. l, with theeccentric turningin the direction of the arrow, it will be understoodthat the pivotal connection of the eccentric rod with the valve rodpermitsthe lower end of said eccentric rod to swing out tothe right ofthe shaft 5, and this movement causes the end 8b of thelink-arm 8, todescribe an arc in a downward direction, thereby causing the valve rodto lower a distance equal to the swing of the lower end of the eccentricrod and its link-arm. This causes the upper steam port to be u'ncovered,as stated, and in the mean time the eccentric strap is lowering awayfrom the rod end, and carries the pins 3a some distance out of thecollars l2, which loosely embrace the same, until the position of theeccentric, shown in Fig. 2, is reached. From this position the pins 3commence to slide back in the collars, but the continued upward movementof the eccentric will swing the lower end of the eccentric rod outlaterally IOO and cause a resultant throw of the valve in the samemanner as just described for the downward swing of the eccentric.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

In a reversing gear for engines, the combination with the valve rod; ofthe main shaft carrying an eccentric, an eccentric strap encircling theshaft eccentric and having opposite upwardly projecting pins, theswinging eccentric rod pivotally connected at its upper end to saidvalve rod and provided at its lower

